Study Purpose:

To investigate the effect of duloxetine for cancer-related neuropathic pain in patients for whom treatment with pregabalin was unsuccessful

Intervention Characteristics/Basic Study Process:

Data were retrospectively reviewed for patients experiencing neuropathic pain who were treated with duloxetine because pregabalin could not be administered, was ineffective, or where the dosage could not be increased due to side effects. Patients were given 20 mg of duloxetine per day, increased to 40 mg/day if needed. Pain was assessed for two weeks.

Sample Characteristics:

The study reported on a sample of 15 patients.

Patient age range was 31–79 years.

The sample was 60% male and 40% female.

Cancer diagnoses included breast, colon, and lung.

Most patients were also receiving strong opioids.

Setting:

Single site

Outpatient setting

Japan

Study Design:

A retrospective study design was used.

Measurement Instruments/Methods:

Numeric rating scale for pain

Results:

Pain was reduced in 7 of the 15 patients. Baseline pain ranged from 5 to 10. After two to four weeks, pain ratings ranged from 2 to 9.

Conclusions:

Duloxetine may be effective for relief of neuropathic pain.

Limitations:

The study has a small sample, with less than 30 participants.

The study has risk of bias due to no control group, no blinding, and no random assignment.

There was no magnitude analysis of individual pain rating changes.

There was no discussion of opioid dose changes, or any use of breakthrough medications.

It appears that pain rating was done at a single time point per week; it is not clear whether this was self-report or of average, current, or worst pain.

Nursing Implications:

Findings suggest that duloxetine may be helpful for patients with neuropathic pain as an alternative to pregabalin. This study provides weak evidence due to multiple study limitations. Further well-designed research is needed to identify the most effective management for cancer-related neuropathic pain.